Impact of ACE2 gene polymorphism on antihypertensive efficacy of ACE inhibitors

Management of Hypertension in the Asia-Pacific Region: A Structured Review

This article reviews available evidence regarding hypertension management in the Asia-Pacific region, focussing on five research questions that deal with specific aspects: blood pressure (BP) control, guideline recommendations, role of renin-angiotensin-aldosterone system (RAAS) inhibitors in clinical practice, pharmacological management and real-world adherence to guideline recommendations. A PubMed search identified 2537 articles, of which 94 were considered relevant. Compared with Europeans, Asians have higher systolic/diastolic/mean arterial BP, with a stronger association between BP and stroke. Calcium channel blockers are the most-commonly prescribed monotherapy in Asia, with significant variability between countries in the rates of angiotensin-converting enzyme inhibitors (ACEis)/angiotensin-receptor blockers (ARBs) and single-pill combination (SPC) use. In clinical practice, ARBs are used more commonly than ACEis, despite the absence of recommendation from guidelines and clinical evidence supporting the use of one class of drug over the other. Ideally, antihypertensive treatment should be tailored to the individual patient, but currently there are limited data on the characteristics of hypertension in Asia-Pacific individuals. Large outcome studies assessing RAAS inhibitor efficacy and safety in multi-national Asian populations are lacking. Among treated patients, BP control rates were ~ 35 to 40%; BP control in Asia-Pacific is suboptimal, and disproportionately so compared with Western nations. Strategies to improve the management of hypertension include wider access/availability of affordable treatments, particularly SPCs (which improve adherence), effective public health screening programs targeting patients to drive health-seeking behaviours, an increase in physician/patient awareness and early implementation of lifestyle changes. A unified Asia-Pacific guideline on hypertension management with pragmatic recommendations, particularly in resource-limited settings, is essential.

A randomized trial of genotype-guided perindopril use

OBJECTIVE

Cough caused by angiotensin-converting enzyme inhibitors (ACEIs) limits their clinical application and cardiovascular benefits. This randomized trial investigated whether genotype-guided perindopril use could reduce drug-related cough in 20 to 79-year-old individuals with hypertension.

METHODS

After screening 120 patients and randomization, 68 were assigned to genotyping ( n  = 41) and control ( n  = 27) groups. NELL1 p.Arg382Trp (rs8176786) and intron (rs10766756) genotype information was used to subdivide the genotyping group into high-risk and low-risk subgroups with at least one or no risk alleles for ACEI-related cough, respectively. The high-risk subgroup received candesartan (8 mg/day) for 6 weeks, whereas the low-risk subgroup received perindopril (4 mg/day). The control group, which was not genotyped, received perindopril (4 mg/day). The primary outcome variables were cough and moderate/severe cough; the secondary outcome variable was any adverse event.

RESULTS

During the 6-week period, the risk of cough was lower in the genotyping group than in the control group [five (12.2%) and nine (33.3%) participants, respectively; hazard ratio: 0.25; log-rank P  = 0.017]. The moderate/severe cough risk was also lower in the genotyping group [one (2.4%) and five (18.5%) participants, respectively; hazard ratio: 0.12; log-rank P  = 0.025]. Differences in cough (hazard ratio: 0.56; log-rank P  = 0.32) and moderate/severe cough risk (hazard ratio: 0.26; log-rank P  = 0.19) between the low-risk and control groups were not significant. The risk of total adverse events was similar between any two groups.

CONCLUSION

Cough risk was lower during genotype-guided treatment than during conventional treatment. These results support the utility of NELL1 variant data in clinical decision making to personalize renin-angiotensin system blocker therapy use.

TRIAL REGISTRATION

ClinicalTrials.gov number: NCT05535595 (retrospectively registered at September 7, 2022).

ACE2 gene polymorphisms are associated with elevated pulmonary artery pressure in congenital heart diseases

BACKGROUNDS

Angiotensin converting enzyme 2 (ACE2) polymorphisms are related to the occurrence and prognosis of cardiovascular disease. However, whether ACE2 polymorphisms also affect pulmonary circulation in congenital heart disease (CHD) remains unclear. Thus, we investigated the relationship between ACE2 single nucleotide polymorphism (SNPs) and pulmonary circulation in CHD patients of Chinese Han ethnicity.

METHODS

Enrolled CHD patients (n = 367) underwent gene sequencing of ACE2 SNPs rs2074192, rs2285666, and rs2106809. Patients with pulmonary hypertension were further examined for detailed hemodynamics.

RESULTS

Female heterozygous patients had worse pulmonary circulation hemodynamic parameters compared to those of homozygotes. Female CHD patients with the CCA (OR = 0.53, 95% CI: 0.32-0.88) or CCG (OR = 0.59, 95% CI: 0.35-0.99) haplotype had a lower risk of elevated pulmonary artery pressure.

CONCLUSION

In female CHD patients, ACE2 SNPs are related to pulmonary circulation hemodynamics. Female CHD patients with the CCA and CCG haplotype had a lower risk of pulmonary hypertension.

No association between genetic markers and hypertension control in multiple cross-sectional studies

We aimed to assess whether genetic markers are associated with hypertension control using two cross-sectional surveys conducted in Lausanne, Switzerland. Management of hypertension was assessed as per ESC guidelines using the 140/90 or the 130/80 mm Hg thresholds. One genetic risk score (GRS) for hypertension (18 SNPs) and 133 individual SNPs related to response to specific antihypertensive drugs were tested. We included 1073 (first) and 1157 (second survey) participants treated for hypertension. The prevalence of controlled participants using the 140/90 threshold was 58.8% and 63.6% in the first and second follow-up, respectively. On multivariable analysis, only older age was consistently and negatively associated with hypertension control. No consistent associations were found between GRS and hypertension control (140/90 threshold) for both surveys: Odds ratio and (95% confidence interval) for the highest vs. the lowest quartile of the GRS: 1.06 (0.71-1.58) p = 0.788, and 1.11 (0.71-1.72) p = 0.657, in the first and second survey, respectively. Similar findings were obtained using the 130/80 threshold: 1.23 (0.79-1.90) p = 0.360 and 1.09 (0.69-1.73) p = 0.717, in the first and second survey, respectively. No association between individual SNPs and hypertension control was found. We conclude that control of hypertension is poor in Switzerland. No association between GRS or SNPs and hypertension control was found.

A Review on COVID-19: Primary Receptor, Endothelial Dysfunction, Related Comorbidities, and Therapeutics

Since December 2019, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a global pandemic named coronavirus disease-19 (COVID-19) and resulted in a worldwide economic crisis. Utilizing the spike-like protein on its surface, the SARS-CoV-2 binds to the receptor angiotensin-converting enzyme 2 (ACE2), which highly expresses on the surface of many cell types. Given the crucial role of ACE2 in the renin–angiotensin system, its engagement by SARS-CoV-2 could potentially result in endothelial cell perturbation. This is supported by the observation that one of the most common consequences of COVID-19 infection is endothelial dysfunction and subsequent vascular damage. Furthermore, endothelial dysfunction is the shared denominator among previous comorbidities, including hypertension, kidney disease, cardiovascular diseases, etc., which are associated with an increased risk of severe disease and mortality in COVID-19 patients. Several vaccines and therapeutics have been developed and suggested for COVID-19 therapy. The present review summarizes the relationship between ACE2 and endothelial dysfunction and COVID-19, also reviews the most common comorbidities associated with COVID-19, and finally reviews several categories of potential therapies against COVID-19.

Association investigations between ACE1 and ACE2 polymorphisms and severity of COVID-19 disease

Due to the unique affinity of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to the angiotensin-converting enzyme 2 (ACE2) receptor in patients, the foremost recent evidence indicated that ACE1 and ACE2 polymorphisms could affect the susceptibility of individuals to SARS-CoV-2 infection and also the disease outcome. Here, we aimed to assess the possible association between two polymorphisms and the severity of disease in patients. In the present study, 146 patients with COVID-19 who were admitted to the Mazandaran University of Medical Sciences hospitals between March 2020 and July 2020 were enrolled in this case-control study. The patients were divided into four groups based on clinical symptoms and severity of the diseases (mild, moderate, severe, and critical). After DNA extraction, the ACE gene I/D polymorphism (rs4646994) and ACE2 gene polymorphism (rs2285666) were genotyped using Gap-PCR and PCR-RFLP techniques, respectively. Then, five samples from each obtained genotype were confirmed by Sanger sequencing technique. Data were analyzed with SAS software version 9.1 using appropriate statistical procedures. The ACE gene I/D polymorphism (rs4646994) genotypes were classified into three types: I/I, I/D, and D/D. Our finding indicated that the prevalence of ACE1 D/D genotype was significantly higher in severe and critical COVID-19 patients (P = 0.0016). Additionally, the analysis revealed a remarkable association between rs4646994 SNP and the HB and ESRI levels in patients (P < 0.05). Although the ACE2 rs2285666 SNP was not related to the severity of disease, this variant was significantly associated with ALT, ESRI, and P. These results provide preliminary evidence of a genetic association between the ACE-D/D genotype and the D allele of ACE1 genotype and the disease severity. Therefore, our findings might be useful for identifying the susceptible population groups for COVID-19 therapy.

An update on angiotensin-converting enzyme 2 structure/functions, polymorphism, and duplicitous nature in the pathophysiology of coronavirus disease 2019: Implications for vascular and coagulation disease associated with severe acute respiratory syndrome coronavirus infection

It has been known for many years that the angiotensin-converting enzyme 2 (ACE2) is a cell surface enzyme involved in the regulation of blood pressure. More recently, it was proven that the severe acute respiratory syndrome coronavirus (SARS-CoV-2) interacts with ACE2 to enter susceptible human cells. This functional duality of ACE2 tends to explain why this molecule plays such an important role in the clinical manifestations of coronavirus disease 2019 (COVID-19). At the very start of the pandemic, a publication from our Institute (entitled "ACE2 receptor polymorphism: susceptibility to SARS-CoV-2, hypertension, multi-organ failure, and COVID-19 disease outcome"), was one of the first reviews linking COVID-19 to the duplicitous nature of ACE2. However, even given that COVID-19 pathophysiology may be driven by an imbalance in the renin-angiotensin system (RAS), we were still far from understanding the complexity of the mechanisms which are controlled by ACE2 in different cell types. To gain insight into the physiopathology of SARS-CoV-2 infection, it is essential to consider the polymorphism and expression levels of the ACE2 gene (including its alternative isoforms). Over the past 2 years, an impressive amount of new results have come to shed light on the role of ACE2 in the pathophysiology of COVID-19, requiring us to update our analysis. Genetic linkage studies have been reported that highlight a relationship between ACE2 genetic variants and the risk of developing hypertension. Currently, many research efforts are being undertaken to understand the links between ACE2 polymorphism and the severity of COVID-19. In this review, we update the state of knowledge on the polymorphism of ACE2 and its consequences on the susceptibility of individuals to SARS-CoV-2. We also discuss the link between the increase of angiotensin II levels among SARS-CoV-2-infected patients and the development of a cytokine storm associated microvascular injury and obstructive thrombo-inflammatory syndrome, which represent the primary causes of severe forms of COVID-19 and lethality. Finally, we summarize the therapeutic strategies aimed at preventing the severe forms of COVID-19 that target ACE2. Changing paradigms may help improve patients' therapy.

Polymorphisms in ACE, ACE2, AGTR1 genes and severity of COVID-19 disease

Background

Infection by the SARS-Cov-2 virus produces in humans a disease of highly variable and unpredictable severity. The presence of frequent genetic single nucleotide polymorphisms (SNPs) in the population might lead to a greater susceptibility to infection or an exaggerated inflammatory response. SARS-CoV-2 requires the presence of the ACE2 protein to enter in the cell and ACE2 is a regulator of the renin-angiotensin system. Accordingly, we studied the associations between 8 SNPs from AGTR1, ACE2 and ACE genes and the severity of the disease produced by the SARS-Cov-2 virus.

Methods

318 (aged 59.6±17.3 years, males 62.6%) COVID-19 patients were grouped based on the severity of symptoms: Outpatients (n = 104, 32.7%), hospitalized on the wards (n = 73, 23.0%), Intensive Care Unit (ICU) (n = 84, 26.4%) and deceased (n = 57, 17.9%). Comorbidity data (diabetes, hypertension, obesity, lung disease and cancer) were collected for adjustment. Genotype distribution of 8 selected SNPs among the severity groups was analyzed.

Results

Four SNPs in ACE2 were associated with the severity of disease. While rs2074192 andrs1978124showed a protector effectassuming an overdominant model of inheritance (G/A vs. GG-AA, OR = 0.32, 95%CI = 0.12–0.82; p = 0.016 and A/G vs. AA-GG, OR = 0.37, 95%CI: 0.14–0.96; p = 0.038, respectively); the SNPs rs2106809 and rs2285666were associated with an increased risk of being hospitalized and a severity course of the disease with recessive models of inheritance (C/C vs. T/C-T/T, OR = 11.41, 95% CI: 1.12–115.91; p = 0.012) and (A/A vs. GG-G/A, OR = 12.61, 95% CI: 1.26–125.87; p = 0.0081). As expected, an older age (OR = 1.47), male gender (OR = 1.98) and comorbidities (OR = 2.52) increased the risk of being admitted to ICU or death vs more benign outpatient course. Multivariable analysis demonstrated the role of the certain genotypes (ACE2) with the severity of COVID-19 (OR: 0.31, OR 0.37 for rs2074192 and rs1978124, and OR = 2.67, OR = 2.70 for rs2106809 and rs2285666, respectively). Hardy-Weinberg equilibrium in hospitalized group for I/D SNP in ACE was not showed (p<0.05), which might be due to the association with the disease. No association between COVID-19 disease and the different AGTR1 SNPs was evidenced on multivariable, nevertheless the A/A genotype for rs5183 showed an higher hospitalization risk in patients with comorbidities.

Conclusions

Different genetic variants in ACE2 were associated with a severe clinical course and death groups of patients with COVID-19. ACE2 common SNPs in the population might modulate severity of COVID-19 infection independently of other known markers like gender, age and comorbidities.

The Impact of ACE2 Polymorphisms on COVID-19 Disease: Susceptibility, Severity, and Therapy

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has currently spread worldwide, leading to high morbidity and mortality. As the putative receptor of SARS-CoV-2, angiotensin-converting enzyme 2 (ACE2) is widely distributed in various tissues and organs of the human body. Simultaneously, ACE2 acts as the physiological counterbalance of ACE providing homeostatic regulation of circulating angiotensin II levels. Given that some ACE2 variants are known to cause an increase in the ligand-receptor affinity, their roles in acquisition, progression and severity of COVID-19 disease have aroused widespread concerns. Therefore, we summarized the latest literature and explored how ACE2 variants and epigenetic factors influence an individual’s susceptibility to SARS-CoV-2 infection and disease outcome in aspects of ethnicity, gender and age. Meanwhile, the possible mechanisms for these phenomena were discussed. Notably, recombinant human ACE2 and ACE2-derived peptides may have special benefits for combating SARS-CoV-2 variants and further studies are warranted to confirm their effects in later stages of the disease process. As the uncertainty regarding the severity and transmissibility of disease rises, a more in-depth understanding of the host genetics and functional characteristics of ACE2 variants will not only help explain individual clinical differences of the disease, but also contribute to providing effective measures to develop solutions and manage future outbreaks of SARS-CoV-2.

Relevance Between COVID-19 and Host Genetics of Immune Response

The outbreak of coronavirus disease 2019 (COVID-19) was caused by the newly emerged corona virus (2019-nCoV alias SARS-CoV-2) that resembles the severe acute respiratory syndrome virus (SARS-CoV). SARS-CoV-2, which was first identified in Wuhan (China) has spread globally, resulting in a high mortality worldwide reaching ~4 million deaths to date. As of first week of July 2021, ~181 million cases of COVID-19 have been reported. SARS-CoV-2 infection is mediated by the binding of virus spike protein to Angiotensin Converting Enzyme 2 (ACE2). ACE2 is expressed on many human tissues; however, the major entry point is probably pneumocytes, which are responsible for synthesis of alveolar surfactant in lungs. Viral infection of pneumocytes impairs immune responses and leads to, apart from severe hypoxia resulting from gas exchange, diseases with serious complications. During viral infection, gene products (e.g. ACE2) that mediate viral entry, antigen presentation, and cellular immunity are of crucial importance. Human leukocyte antigens (HLA) I and II present antigens to the CD8⁺ and CD4⁺ T lymphocytes, which are crucial for immune defence against pathogens including viruses. HLA gene variants affect the recognition and presentation of viral antigenic peptides to T-cells, and cytokine secretion. Additionally, endoplasmic reticulum aminopeptidases (ERAP) trim antigenic precursor peptides to fit into the binding groove of MHC class I molecules. Polymorphisms in ERAP genes leading to aberrations in ERAP’s can alter antigen presentation by HLA class I molecules resulting in aberrant T-cell responses, which may affect susceptibility to infection and/or activation of immune response. Polymorphisms from these genes are associated, in global genetic association studies, with various phenotype traits/disorders many of which are related to the pathogenesis and progression of COVID-19; polymorphisms from various genes are annotated in genotype-tissue expression data as regulating the expression of ACE2, HLA’s and ERAP’s. We review such polymorphisms and illustrate variations in their allele frequencies in global populations. These reported findings highlight the roles of genetic modulators (e.g. genotype changes in ACE2, HLA’s and ERAP’s leading to aberrations in the expressed gene products or genotype changes at other genes regulating the expression levels of these genes) in the pathogenesis of viral infection.

Molecules in pathogenesis: angiotensin converting enzyme 2 (ACE2)

The renin-angiotensin system is mainly associated with the regulation of blood pressure, but recently many other functions of this system have been described. ACE2, an 805-amino acid monocarboxypeptidase type I transmembrane glycoprotein, was discovered in 2000 and has sequence similarity to two other proteins, namely ACE and collectrin. The ACE2 gene is located on Xp22 and is highly polymorphic. ACE2 is expressed in numerous tissues especially the lung alveolar epithelial cells, heart, kidney and gastrointestinal tract. Animal studies have found that ACE2 is central in diseases affecting almost all organ systems, among other cardiac, respiratory, renal and endocrine functions. ACE2 was identified as the cellular contact point for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the global pandemic (COVID-19), and is a potential drug target. SARS-CoV-2 infection has several effects on the renin-angiotensin system and conversely, regulation of this receptor may affect the progress of infection. We describe the genetics and functions of ACE2, explore its various physiological functions in the renin-angiotensin system and discuss its role in the pathophysiology of disease. ACE2 opposes the vasopressor ACE pathway of the renin-angiotensin system by converting angiotensin (Ang) I to Ang (1-9) and Ang II to Ang (1-7) which initiates the vasodilatory pathway. ACE2 may have a protective effect in the lung and kidney as knockout mice display susceptibility to acute respiratory distress and hypertensive nephropathy. Binding of SARS-CoV-2 and the subsequent fusion and downregulation of this pathway during SARS-CoV-2 infection may explain some of the unusual sequelae seen in COVID-19.

A comprehensive guide to the pharmacologic regulation of angiotensin converting enzyme 2 (ACE2), the SARS-CoV-2 entry receptor

The recent emergence of coronavirus disease-2019 (COVID-19) as a global pandemic has prompted scientists to address an urgent need for defining mechanisms of disease pathology and treatment. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent for COVID-19, employs angiotensin converting enzyme 2 (ACE2) as its primary target for cell surface attachment and likely entry into the host cell. Thus, understanding factors that may regulate the expression and function of ACE2 in the healthy and diseased body is critical for clinical intervention. Over 66% of all adults in the United States are currently using a prescription drug and while earlier findings have focused on possible upregulation of ACE2 expression through the use of renin angiotensin system (RAS) inhibitors, mounting evidence suggests that various other widely administered drugs used in the treatment of hypertension, heart failure, diabetes mellitus, hyperlipidemias, coagulation disorders, and pulmonary disease may also present a varied risk for COVID-19. Specifically, we summarize mechanisms on how heparin, statins, steroids and phytochemicals, besides their established therapeutic effects, may also interfere with SARS-CoV-2 viral entry into cells. We also describe evidence on the effect of several vitamins, phytochemicals, and naturally occurring compounds on ACE2 expression and activity in various tissues and disease models. This comprehensive review aims to provide a timely compendium on the potential impact of commonly prescribed drugs and pharmacologically active compounds on COVID-19 pathology and risk through regulation of ACE2 and RAS signaling.

Clinical impact of echocardiography parameters and molecular biomarkers in heart failure: Correlation of ACE2 and MCP-1 polymorphisms with echocardiography parameters: A comparative study

Heart failure is still the leading cause of hospitalization in patients over 65 years of age and is defined as a multifactorial pathology which involves environmental factors and also genetic predispositions. The aim of the present study was to evaluate a possible correlation between single nucleotide polymorphisms (SNPs) of angiotensin converting enzyme 2 (ACE2) and monocyte chemoattractant protein-1 (MCP-1) genes and cardiac remodeling in Caucasian patients diagnosed with heart failure. Our comparative translational research study included 116 patients diagnosed with heart failure and was carried out in Cluj-Napoca, Romania between September 2017 and March 2019. Three SNPs, namely rs4646156, rs4646174 and rs1024611, were genotyped using a Taqman real-time PCR technique. Our results showed that carriers of the AA genotype for ACE2 rs4646156 had a significant dilatation of the left ventricle (LV) with signs of LV hypertrophy (LVH), while TT carriers had a significant left atrial dilatation. For ACE2 rs4646174, homozygotes for the C allele presented a dilated LV with signs of LVH with statistical significance and had a tendency towards a lower ejection fraction. MCP-1 rs1024611 AA variant carriers had a significant LVH in the dominant model. In conclusion, our study showed a strong association between echocardiographic parameters of cardiac remodeling and SNPs rs4646156, rs4646174 of ACE2 and rs1024611 of MCP-1.

Attenuating the Effects of Novel COVID-19 (SARS-CoV-2) Infection-Induced Cytokine Storm and the Implications

The COVID-19 pandemic constitutes an arduous global health challenge, and the increasing number of fatalities calls for the speedy pursuit of a remedy. This review emphasizes the changing aspects of the COVID-19 disease, featuring the cytokine storm's pathological processes. Furthermore, we briefly reviewed potential therapeutic agents that may modulate and alleviate cytokine storms. The literature exploration was made using PubMed, Embase, MEDLINE, Google scholar, and China National Knowledge Infrastructure databases to retrieve the most recent literature on the etiology, diagnostic markers, and the possible prophylactic and therapeutic options for the management of cytokine storm in patients hospitalized with COVID-19 disease. The causative agent, severe acute respiratory coronavirus-2 (SARS-CoV-2), continually threatens the efficiency of the immune system of the infected individuals. As the first responder, the innate immune system provides primary protection against COVID-19, affecting the disease's progression, clinical outcome, and prognosis. Evidence suggests that the fatalities associated with COVID-19 are primarily due to hyper-inflammation and an aberrant immune function. Accordingly, the magnitude of the release of pro-inflammatory cytokines such as interleukin (IL)-1, (IL-6), and tumor necrosis alpha (TNF-α) significantly differentiate between mild and severe cases of COVID-19. The early prediction of a cytokine storm is made possible by several serum chemistry and hematological markers. The prompt use of these markers for diagnosis and the aggressive prevention and management of a cytokine release syndrome is critical in determining the level of morbidity and fatality associated with COVID-19. The prophylaxis and the rapid treatment of cytokine storm by clinicians will significantly enhance the fight against the dreaded COVID-19 disease.

ACE2 and TMPRSS2 polymorphisms in various diseases with special reference to its impact on COVID-19 disease

Background

A carboxypeptidase protein called ACE2 is found in many organs. ACE2 protein can play a pivotal role to regulate the pathological changes of several diseases including COVID-19. TMPRSS2 gene is expressed in many human tissues and plays a critical role in spreading the infection of the viruses including coronavirus and progression of prostate cancer, and hence could be used as a potential drug target. There are limited reports on occurrence of genetic polymorphism of ACE2 and TMPRSS2 in general population, expressions in pathological conditions, and its impact on COVID-19 disease. Hence we comprehended the occurrence of ACE2, TMPRSS2 polymorphism in general population, expression in various diseases and its impact on COVID-19 disease.

Method

We utilized multiple databases, PubMed (Medline), EMBASE and Google Scholar for literature search.

Description

ACE2 polymorphisms have significant linkages with various diseases, including severity of SARS-CoV-2 infection. Genetic variations of these genes contribute to individual's genetic susceptibility to viral infection and its subsequent clearance. The diversity and variations in the population distribution of these genes, might greatly influence and in turn reflect into the observed population and gender differences of the severity and clinical outcomes of SARS-CoV-2 infection.

Conclusion

There are diversities in distribution of ACE2 and TMPRSS2 polymorphisms among different populations. Analyzing the genetic variants and expression of ACE2 and TMPRSS2 genes, in a population may provide the genetic marker for susceptibility or resistance against the coronavirus infection, which might be useful for identifying the susceptible population groups for targeted interventions and for making relevant public health policy decisions.

COVID-19 and Sex Differences: Mechanisms and Biomarkers

Men are consistently overrepresented in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and coronavirus disease 2019 (COVID-19) severe outcomes, including higher fatality rates. These differences are likely due to gender-specific behaviors, genetic and hormonal factors, and sex differences in biological pathways related to SARS-CoV-2 infection. Several social, behavioral, and comorbid factors are implicated in the generally worse outcomes in men compared with women. Underlying biological sex differences and their effects on COVID-19 outcomes, however, have received less attention. The present review summarizes the available literature regarding proposed molecular and cellular markers of COVID-19 infection, their associations with health outcomes, and any reported modification by sex. Biological sex differences characterized by such biomarkers exist within healthy populations and also differ with age- and sex-specific conditions, such as pregnancy and menopause. In the context of COVID-19, descriptive biomarker levels are often reported by sex, but data pertaining to the effect of patient sex on the relationship between biomarkers and COVID-19 disease severity/outcomes are scarce. Such biomarkers may offer plausible explanations for the worse COVID-19 outcomes seen in men. There is the need for larger studies with sex-specific reporting and robust analyses to elucidate how sex modifies cellular and molecular pathways associated with SARS-CoV-2. This will improve interpretation of biomarkers and clinical management of COVID-19 patients by facilitating a personalized medical approach to risk stratification, prevention, and treatment.

COVID-19: The Influence of ACE Genotype and ACE-I and ARBs on the Course of SARS-CoV-2 Infection in Elderly Patients

Since the beginning of 2020, the whole world has been struggling with the pandemic of Coronavirus Disease 2019 (COVID-19) caused by a novel coronavirus SARS-CoV-2. The SARS-CoV-2 infection depends on ACE2, TMPRSS2, and CD147, which are expressed on host cells. Several studies suggest that some single nucleotide polymorphisms (SNPs) of ACE2 might be a risk factor of COVID-19 infection. Genotypes affect ACE2 structure, its serum concentration, and levels of circulating angiotensin (1-7). Moreover, there is evidence that ACE genotype affects the outcomes of acute respiratory distress syndrome (ARDS) treatment, the most severe consequence of SARS-CoV-2 infection. COVID-19 morbidity, infection course, and mortality might depend on ACE D allele frequency. The aim of this narrative review was to analyze and identify the mechanisms of ACE-I and ARBs with particular emphasis on angiotensin receptors and their polymorphism in the light of COVID-19 pandemic as these medications are commonly prescribed to elderly patients. There is no direct evidence yet for ACE-I or ARBs in the treatment of COVID-19. However, for those already taking these medications, both the European Society of Cardiology and the American College of Cardiology recommend continuing the treatment, because at present, there is no clear clinical or scientific evidence to justify the discontinuation of ACE-I or ARBs. Individualized treatment decisions should be based on the clinical condition and co-morbidities of each patient.

Angiotensin converting enzyme: A review on expression profile and its association with human disorders with special focus on SARS-CoV-2 infection

Angiotensin-converting enzyme (ACE) and its homologue, ACE2, have been mostly associated with hypertensive disorder. However, recent pandemia of SARS-CoV-2 has put these proteins at the center of attention, as this virus has been shown to exploit ACE2 protein to enter cells. Clear difference in the response of affected patients to this virus has urged researchers to find the molecular basis and pathophysiology of the cell response to this virus. Different levels of expression and function of ACE proteins, underlying disorders, consumption of certain medications and the existence of certain genomic variants within ACE genes are possible explanations for the observed difference in the response of individuals to the SARS-CoV-2 infection. In the current review, we discuss the putative mechanisms for this observation.

ACE2 receptor polymorphism: Susceptibility to SARS-CoV-2, hypertension, multi-organ failure, and COVID-19 disease outcome

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged in Chinese people in December 2019 and has currently spread worldwide causing the COVID-19 pandemic with more than 150,000 deaths. In order for a SARS-CoV like virus circulating in wild life for a very long time to infect the index case-patient, a number of conditions must be met, foremost among which is the encounter with humans and the presence in homo sapiens of a cellular receptor allowing the virus to bind. Recently it was shown that the SARS-CoV-2 spike protein, binds to the human angiotensin I converting enzyme 2 (ACE2). This molecule is a peptidase expressed at the surface of lung epithelial cells and other tissues, that regulates the renin-angiotensin-aldosterone system. Humans are not equal with respect to the expression levels of the cellular ACE2. Moreover, ACE2 polymorphisms were recently described in human populations. Here we review the most recent evidence that ACE2 expression and/or polymorphism could influence both the susceptibility of people to SARS-CoV-2 infection and the outcome of the COVID-19 disease. Further exploration of the relationship between the virus, the peptidase function of ACE2 and the levels of angiotensin II in SARS-CoV-2 infected patients should help to better understand the pathophysiology of the disease and the multi-organ failures observed in severe COVID-19 cases, particularly heart failure.

ACE2 as Drug Target of COVID-19 Virus Treatment, Simplified Updated Review

Background

Since its first appearance in December of 2019, regular updates around the world demonstrates that the number of new Corona Virus 2019 (COVID-19) cases are increasing rapidly, indicating that not only does COVID-19 exhibit a rapid spread pattern, but human intervention is necessary for its resolution. Up until today (27-5-2020) and according to the World Health Organization (WHO), the number of confirmed COVID-19 cases has surpassed 4.5 million with more than 307, 500 deaths. Almost all countries have been affected by COVID-19, and resultingly, various drug trials have been conducted, however, a targeted treatment remains to be made accessible to the public. Recently, Angiotensin-Converting Enzyme-2 (ACE2) has gained some attention for its discovery as a potential attachment target of COVID-19.

Methods

We reviewed the most recent evidence regarding ACE2 distribution and action, the binding mechanism of COVID-19 and its correlation to cellular injury, ACE2 polymorphisms and its association to fatal COVID-19 and susceptibility and, finally, current ACE2-based pharmacotherapies against COVID-19.

Results

Blocking the ACE2 receptor-binding domain (RBD) using a specific ligand can prevent COVID-19 from binding, and consequently cellular entry and injury. Comparatively, soluble ACE2, which has a higher affinity to COVID-19, can neutralize COVID-19 without affecting the homeostatic function of naturally occurring ACE2. Lastly, ACE2 mutations and their possible effect on the binding activity of COVID-19 may enable researchers to identify high-risk groups before they become exposed to COVID-19.

Conclusion

ACE2 represents a promising target to attenuate or prevent COVID-19 associated cellular injury.

Hypertension and hypertensive left ventricular hypertrophy are associated with ACE2 genetic polymorphism

AIMS

Renin-angiotensin system modulates cardiac structure independent of blood pressure. The present study aimed at investigating whether single nucleotide polymorphism (SNP) and haplotype of angiotensin converting enzyme 2 (ACE2) could influence blood pressure and the susceptibility to hypertensive left ventricular hypertrophy (LVH).

SUBJECTS AND METHODS

A total of 647 patients (347 females and 300 males) with newly diagnosed mild to moderate essential hypertension were enrolled in a blood pressure matched, case-control study. Four ACE2 tagSNPs (rs2074192, rs4646176, rs4646155 and rs2106809) were genotyped and major haplotypes consisting of these four SNPs were reconstructed for all subjects.

KEY FINDINGS

In females, minor alleles of ACE2 rs2074192 and rs2106809 respectively conferred a 2.1 and 2.0 fold risk for LVH. ACE2 haplotype TCGT increased the risk for LVH while another haplotype CCGC decreased the risk in females. The covariates-adjusted mean left ventricular mass index was 11% greater in TCGT haplotype carriers than in noncarriers in women. In females, the covariates-adjusted mean systolic blood pressure was 3.4 mm Hg lower in CCGC haplotype carriers than in noncarriers. In males, the covariates-adjusted mean systolic blood pressure was 2.4 mm Hg lower in CCGC haplotype carriers than in noncarriers.

SIGNIFICANCE

ACE2 tagSNPs rs2074192 and rs2106809 as well as major haplotypes CCGC and TCGT may serve as novel risk markers for LVH in hypertensive patients.

A Systematically Assembled Signature of Genes to be Deep-Sequenced for Their Associations with the Blood Pressure Response to Exercise

: Background: Exercise is one of the best nonpharmacologic therapies to treat hypertension. The blood pressure (BP) response to exercise is heritable. Yet, the genetic basis for the antihypertensive effects of exercise remains elusive. Methods: To assemble a prioritized gene signature, we performed a systematic review with a series of Boolean searches in PubMed (including Medline) from earliest coverage. The inclusion criteria were human genes in major BP regulatory pathways reported to be associated with: (1) the BP response to exercise; (2) hypertension in genome-wide association studies (GWAS); (3) the BP response to pharmacotherapy; (4a) physical activity and/or obesity in GWAS; and (4b) BP, physical activity, and/or obesity in non-GWAS. Included GWAS reports disclosed the statistically significant thresholds used for multiple testing. Results: The search yielded 1422 reports. Of these, 57 trials qualified from which we extracted 11 genes under criteria 1, 18 genes under criteria 2, 28 genes under criteria 3, 27 genes under criteria 4a, and 29 genes under criteria 4b. We also included 41 genes identified from our previous work. Conclusions: Deep-sequencing the exons of this systematically assembled signature of genes represents a cost and time efficient approach to investigate the genomic basis for the antihypertensive effects of exercise.

Association of ACE2 genetic polymorphisms with hypertension-related target organ damages in south Xinjiang

Essential hypertension (EH) is a principal contributing factor in worldwide cardiovascular disease mortality. Although interventions that minimize environmental risk factors for EH are associated with reduced cardiovascular disease, such approaches are limited for individuals with high genetic EH risk. In this study, we investigated possible associations between ACE2 polymorphisms and hypertension-related target organ damages in south Xinjiang, China. Four hundred and two hypertensive patients were enrolled as study participants in an EH group, and 233 normotensive individuals were enrolled as control subjects. Participants were recruited from the south Xinjiang region. Fourteen ACE2 polymorphisms were genotyped by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Risk genotypes of rs2074192 (TT+CT, OR = 1.72, 95% CI: 1.17–2.53), rs2106809 (TT, OR = 1.71, 95% CI: 1.13–2.58), rs4240157 (CC+CT, OR = 1.99, 95% CI: 1.17–3.41), rs4646155 (TT+CT, OR = 1.94, 95% CI: 1.06–3.54), rs4646188 (TT+CT, OR = 3.25, 95% CI: 1.95–5.41), rs4830542 (CC+CT, OR = 1.88, 95% CI: 1.10–3.23), and rs879922 (CC+CG, OR = 4.86, 95% CI: 2.74–8.64) were associated with EH. Hypertensive patients carrying the control genotype of rs2074192 (CC, OR = 2.37, 95% CI: 1.28–4.39) were associated with CAS ≥50%, while those carrying a high-EH-risk genotype of rs4240157 (OR = 2.62, 95% CI: 1.24–5.54), rs4646155 (OR = 2.44, 95% CI: 1.16–5.10), or rs4830542 (CC+CT, OR = 2.20, 95% CI: 1.03–4.69) were associated with atrial fibrillation (AF), larger left atrial diameter, and higher levels of renin–angiotensin–aldosterone system (RAAS) activation (renin and angiotensin I/II). In conclusion, the ACE2 variant rs2074192 was associated with EH and EH with CAS ≥50%, while 3 ACE2 variants (rs4240157, rs4646155, and rs4830542) were associated with EH- and hypertension-related AF and left atrial remodeling in south Xinjiang, China.

Association of ACE2 polymorphisms with susceptibility to essential hypertension and dyslipidemia in Xinjiang, China

Background

Cardiovascular benefits by reversing environmental risks factors for essential hypertension (EH) and dyslipidemia could be weaken by high genetic risk. We investigated possible associations between ACE2 polymorphisms and dyslipidemia in patients with EH.

Methods

Four hundred and two hypertensive patients were enrolled in an EH group and 233 normotensive individuals were enrolled as control group from the Xinjiang region of China. Fourteen ACE2 polymorphisms were genotyped by Matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

Results

Participants carrying T allele (TT + CT) of rs2074192 (P = 0.006), rs4646155 (P = 0.030) and rs4646188 (P < 0.001), C allele (CT + CT or CC + CG) of rs4240157 (P = 0.012), rs4830542 (P = 0.020) and rs879922 (P < 0.001) and TT genotype of rs2106809 (P = 0.012) were associated with EH. Meanwhile,ACE2 SNPs also exhibited association with dyslipidemia but exhibited obvious heterogeneity. rs1978124 (TT + CT, P = 0.009), rs2106809 (TT, P = 0.045), rs233575 (CC + CT, P = 0.018), rs4646188 (CC, P = 0.011) and rs879922 (CC + CG, P = 0.003) were association with increased LDL-C (≥1.8 mmol/L). rs2106809 (CC + CT, P < 0.001), rs2285666(TT + CT, P = 0.017), rs4646142(CC + CG, P = 0.044), rs4646155(TT + CT, P < 0.001) and rs4646188(TT + CT, P = 0.033) were association with decreased HDL-C (< 1.0 mmol/L). rs2074192 (TT + CT, P = 0.012), rs4240157 (CC + CT, P = 0.027), rs4646156 (AA+AT, P = 0.007), rs4646188 (TT + CT, P = 0.005), rs4830542 (CC + CT, P = 0.047) and rs879922 (CC + CG, P = 0.001) were association with increased TC (≥5.2 mmol/L). rs2106809 (P = 0.034) and rs4646188 (P = 0.013) were associated with hypertriglyceridemia. Further, ischemic stroke was more prevalent with rs4240157 (CC + CT, P = 0.043), rs4646188 (CC + CT, P = 0.013) and rs4830542 (CC + CT, P = 0.037). In addition, rs2048683 and rs6632677 were not association with EH, dyslipidemia and ischemic stroke.

Conclusion

The ACE2 rs4646188 variant may be a potential and optimal genetic susceptibility marker for EH, dyslipidemia and its related ischemic stroke.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0890-6) contains supplementary material, which is available to authorized users.

Relationship between genetic variants of ACE2 gene and circulating levels of ACE2 and its metabolites

WHAT IS KNOWN

Angiotensin-converting enzyme 2 (ACE2) plays an important role in the development of essential hypertension (EH). Genetic factors remarkably influence circulating ACE2 level.

OBJECTIVE

Because heritability had remarkable effects on circulating ACE2, we designed this study to shed light on whether circulating levels of ACE2, angiotensin-(1-7) and angiotensin-(1-9) were linked to single nucleotide polymorphisms (SNPs) and haplotypes in ACE2 gene.

METHODS

A total of 213 patients with newly diagnosed mild to moderate EH were enrolled in the present study. Four ACE2 tag SNPs (rs2074192, rs4646171, rs4646155 and rs2106809) were genotyped, and major haplotypes consisting of these 4 SNPs were reconstructed for all subjects. Circulating levels of ACE2, angiotensin-(1-7) and angiotensin-(1-9) were measured using enzyme-linked immunosorbent assay.

RESULTS

In female subjects, linear regression analysis suggested that rare alleles of ACE2 rs2074192 and rs2106809 were associated with reduced circulating angiotensin-(1-7) levels (P=.007 and P=.006, respectively). ACE2 haplotype CAGC was associated with elevated circulating angiotensin-(1-7) levels (P=.03) whereas TAGT was associated with reduced circulating angiotensin-(1-7) levels in females (P<.001). Univariate linear regression analysis revealed that circulating ACE2 levels were positively associated with systolic blood pressure (P=.02), mean arterial pressure (P=.02) and serum creatinine (P<.001) in females whereas circulating ACE2 levels were positively associated with age (P<.001) and serum creatinine (P<.001) in males.

WHAT IS NEW AND CONCLUSION

ACE2 SNPs and haplotypes are associated with circulating angiotensin-(1-7) levels. ACE2 genetic variants may be the determinants of circulating angiotensin-(1-7) levels in hypertensive females.